Acrobits is a privately owned software development company creating VoIP Clients for mobile platforms, based in Prague, Czech Republic.
Acrobits was founded in November 2008, and builds mobile VoIP software with a polished user interface, supporting encrypted calls using SRTP/SDES and ZRTP, Google Voice integration, and the G.729 Annex A audio codec.
Acrobits Softphone is the leading SIP Client on the App Store, featuring push notifications and the G.729 Annex A audio codec, backgrounding, Google Voice integration and encrypted calls through ZRTP.
As soon as the app is suspended to background or exited completely, SIPIS server takes over, registers the account and starts listening for incoming calls.
The advantage of this solution is that the mobile app does not need to run at all on the device, consuming no additional battery power, and is still able to receive incoming calls.
The media of the call (audio and video) are still transferred directly to the mobile app, for lowest latency and security - no extra relaying is done.
Acrobits Softphone supports encrypted voice and video calls using the standard SRTP protocol.